Counterbalancing lid support



June 3, 1969 w, co I 3,447,190

COUNTERBA LANCING LID SUPPORT Filed Oct. 25, 1967 United States PatentUS. Cl. 16-1 6 Claims ABSTRACT OF THE DISCLOSURE A counterbalancing lidsupport designed to support lids of school desk size and weight having ametal cover or housing secured within the pan of the desk and housing aplastic liner. A compression spring is positioned within the liner and arod has a T-bar at one end fitting in a swivel mounted on the desk lidand a partial spherical member at the opposite end received in theplastic liner and abutting one end of the spring. Different weight lidscan be accommodated with this lid support merely by changing themounting location on the desk lid and pan.

The present invention relates to a counterbalancing lid support and moreparticularly to a lid support used on the lids of school desk size andweight.

In school rooms, a common type ofdesk for a child utilizes a desk pan orreceptaclegenerally formed of metal which is of a generally dished shapeto store the books, pencils and other school supplies. The desk has alid hinged adjacent the rear edge of the pan and which is lifted toobtain access to the contents or to replace school materials. As thedesk lid is freely hinged, accidents occur where the lid isinadvertently released or dropped and which may injure a child if hishead or other portion of his body is in the way of the lid such as ifhis fingers are between the lid and the edge of the desk pan. Thepresent invention obviates these problems by providing a lid supporthaving means to prevent the lid from falling closed under its ownweight.

Among the objects of the present invention is the provision of acounterbalancing lid support to support lids of school desk size so thatthe lid cannot fall closed from its own weight. The lid support includesa rod having one end received in a metal cover or housing secured to thedesk pan and this end abutting an end of a compression spring housedwithin a plastic liner in the cover. The opposite end of the rod ismounted in a swivel secured to the underside of the desk lid. Theplastic liner is positioned in the cover and houses the spring toprevent the spring from rubbing or frictional contact with the interiorof the metal cover and thus avoid noise incident to metal-to-metalcontact.

Another object of the present invention is the provision of acounterbalancing lid support having a swivel mounting on the lid ofthedesk providing a wide contact area with a T-bar or arm formed on theend of the rod. The broad contact area prevents excessive wear thereatwhich has been a problem of prior lid supports. No friction is utilizedas a part of the control as the spring acting on the rod provides all ofthe counterbalancing force.

A further object of the present invention is the provision of acounterbalancing lid support having a selfaligning swivel provided by arounded enlarged end or partial spherical member formed or provided onthe end of the rod received in the cover and liner. The ball shape onthe rod acts as a swivel on the spring and also adds a self-aligningfeature to the rod.

The present invention also comprehends the provision of acounterbalancing lid support for school desk lids having a housingsecured to the interior side surface of the desk pan and a swivelconnection secured to the underside of the lid. With this arrangement ofparts, different weight lids can be accommodated just by changing themounting location on the lid and pan.

Further objects are to provide a construction of maximum simplicity,efliciency, economy and ease of assembly and operation, and such furtherobjects, advantages and capabilities as will later more fully appear andare inherently possessed thereby.

In the drawings: 7

FIGURE 1 is an enlarged perspective view of the counterbalancing lidsupport operatively mounted on the desk pan and the desk lid with thelid open position.

FIG. 2 is a front elevational view of the counterbalancing lid supportwith the rod and swivel mounting shown in one position in solid linesand in a second position in dotted lines.

FIG. 3 is a top plan view of the counterbalancing lid support of FIGS. 1and 2 with the lid and swivel omitted.

FIG. 4 is a horizontal cross sectional view taken on the line 4--4 ofFIG. 2.

Referring more particularly to the disclosure in the drawing wherein isshown an illustrative embodiment of the present invention, FIG. 1discloses a counterbalancing lid support 10 mounted within and on a sideWall of the pan 11 of a desk and secured to the desk lid 12 which ishingedly mounted at 13 to the rear Wall of the pan 11. The lid support10 includes a metal cover or housing 14 having a front wall 15, parallelside walls 16, 16 and mounting flanges 17, 17 integral with the sidewalls 16, 1-6 and having openings receiving suitable attaching means,such as the screws 18. The cover has a closed lower end 19 formed byinturned flanges and the upper end is provided with a pair of inturnedflanges 21, 21, the flanges at the opposite ends being integral with theside walls 16, 16.

Each flange 21 is provided with a pair of parallel legs 22, 23 definingtherebetween a central slot 24, the legs 23, 23 of each flange beingshorter than the leg 22 so as to provide an intermediate slot 25 openinginto slots 24, 24 to form a T-shaped recess (FIG. 3). Conformablypositioned within the cover 14 is a liner 26 formed of a suitableplastic material which has a lower open end 27 abutting the closed end19 of the cover and an enlarged open upper end at 28, the liner 26housing a compression spring 29 therein. One end of the spring 29 abutsthe lower closed end 19 of the cover and the other end extends upward toadjacent the upper end 28 of the liner 26.

An arm or rod 31 extends between the cover 14 and a swivel mounting 32on the desk lid with the arm 31 terminating at one end in a T-bar 33fitting within a swivel bracket 34 of the swivel mounting 32 secured tothe underside of the lid 12 by suitable fastening means such as screws35. The bracket 34 has a raised transverse central portion 36 receivingthe T-bar 33, and a longi-' tudinal slot 37 across the raised portion 36receives the end of arm 31 to allow for pivotal motion of the arm.

The opposite end of the arm 31 terminates in a rounded enlargement orpartial spherical part 38 having its rounded surface 39 abutting theupper end of the compression spring 29. The ball shape 38 on the rod 31acts as a swivel on the end of the spring 29 and also adds aself-aligning feature to the support unit. The plastic liner 26 isutilized to guide the spring 29 and rod 31 and to prevent the springfrom frictional contact with or rubbing on the interior of the metalcover and making noise incident to metal-to-metal contact The slots 24,24 are aligned in the cover 14 to receive the arm 31 and allow theswivel action of the arm when the lid 12 is moved relative to the deskpan 11. Also, the wide contact area of the shown in fully tion relativeto the desk pan 11 and the compression spring 29 acting against the arm31 retains the lid in its open position. When the lid 12 is beingclosed, the ball 38 on the arm 31 travels down within the liner 26depressing the spring 29. When the lid 12 is fully closed, the spring 29and arm 31 remain in this position until the lid is manually lifted.When the lid is opened, the spring 29 exerts force against the ball 38to counterbalance and prevent the lid from falling closed from its ownweight. By this arrangement, different Weights of lids can beaccommodated just by changing the mounting location of the support 10 onthe desk lid 12 and desk pan 11.

Having thus disclosed my invention, I claim:

1. A counterbalancing lid support for the lid of a desk having a deskpan with the lid hingedly mounted thereon, comprising an elongated coversecured to the interior surface of the desk pan and having a closedlower end and a slotted upper end, a plastic liner positioned in saidcover, a compression spring received in said liner, a reciprocable armhaving a round enlargement at one end abutting said compression springin the cover to provide a swivel for the arm on said spring and theopposite end pivotally connected to said desk lid, and a swivel bracketsecured to the underside of the desk lid and receiving said lastmentioned end of said arm.

2. A counterbalancing lid support as set forth in claim 1, in which saidcover has a front wall and side walls with outwardly extending mountingflanges and end flanges integral with said side walls providing aclosure at the ends of the cover, the upper end flanges being .4slot-ted for receiving and allowing swivelling movement of said arm.

3. A counterbalancing lid support as set forth in claim 1, in which saidrounded enlargement on the one end of said arm is positioned within saidliner and cover.

4. A counterbalancing lid support as set forth in claim 1, in which saidarm terminates at its upper end in a T-bar received in said swivelbracket to provide unidirectional swivelling movement of the armrelative to the lid.

5. A counterbalancing lid support as set forth in claim 4, in which saidswivel bracket includes a raised transverse portion receiving said T-barand has an elongated slot intersecting and transverse to the axis of theraised portion.

6. A counterbalancing lid support as set forth in claim 3, in which saidrounded enlargement on the end of the arm is a partial spherical member.

References Cited UNITED STATES PATENTS 1,712,648 5/1929 Campbell.

2,641,795 6/1953 James et al. l'6--85 XR 2,843,226 7/1958 Nordmark 108-6XR FOREIGN PATENTS 33,697 4/ 1934 Netherlands.

BOBBY R. GAY, Primary Examiner.

J. L. KOHNEN, Assistant Examiner.

US. Cl. X.R. 16-85

